Process of polishing glass and apparatus therefor



1,621,297 F. B. WALDRON PocEss 0F POLISHING GLASS AND APPARATUS THEREFOR March 15, 1927.

FREDERIC BARNES WALDRON, OF PRESCOT, ENGLAND, ASSIGNOR TOJPILKINGTON BROTHERS LIM ITED, OF LIVERPOOL, ENGLAND, A COMPANY OF ENG-LAN lT'iiOCESS-OF POLISHING GLASS AND APPARATUS THEREFOR.

Original application'filed November 11', 1924, Serial No. 749,138, and in Great Britain November 23', 1923.

Divided and this application filed June 10, 1926. Serial No. 115,118;

This invention relates to continuous grinding and polishing of a series of plates of glass and apparatus therefor, and has for I its object improved methodsand apparatus whereby the polishing is done in a shorter time and with less expenditure of power than has heretofore obtained with other mrthods.

In the following specification'and claims,

0 the term continuous polishing as applied t methods or apparatus is used to mean the polishing of a strip of glass or a series of plates of glass forming a practically continuous strip which is moved in the direc- 16 tion of its length, and is subjected to the action of tion.

The term runner when not specifically characterized is used to mean a polishing runner of any known type adapted to the work, V'liether rotary or reciprocating or both. The term stationary when applied to a runner is used to mean stationary in respect to travel only. i

In the continuous polishing apparatus as heretofore employed, the strip of glass is passed slowly under a series .of stationary runners. Each runner therefore is always performing the same work with the same abrasive or polishing medium on glass which is in the same stage of the polishing operation. i

' Now it is found that polishing isbest effected when each runner passes'through a series of stages in which the treatment and consequentlythe condition of its polishing surfaces, difi'er. Customarily there are three such stages, one in which the rouge is Washed out of the surfaces by a plentiful supply of water, a second in which rouge and water are supplied to the polishing surfaces, and a third in which water only is supplied while the rouge impregnating the surface, effects the polishing, suflic'ient water only being supplied as a lubricant. To effect good and rapid polishing, each runner must pass successively through these three stages and each section of glass must be operated on successively by polishing runners having their sur faces in the condition of these three stages.

' According to this invention, the runners as well as the strip of glass are caused to travel continuously and each runner operates in succession over one and the same olishinrunners durin its mo length of strip, with its polishing surfaces in the different conditions which are produced by the different treatments.

In the accompanying drawings Figure 1 is a diagrammatic plan view (partly broken away) of a continuous polishing invention;

Figure 2 is a transverse section cf the glass-carrying tables on their guides, showing a runner frame in elevation and Figures 3 and 4 are diagrams indicating a polishing operation.

The series of glass-carrying tables 1 are moved on their guides 2-in the direction of the arrow in Figure 1,1i'n the customary manner, the means for removing tables from, and adding them to, the series, not being shown.

apparatus according to the present Polishing'runners 3 mounted in frames 4 are adapted to travel along the line of theach runner frame 4 tables 1, on rails 5. I may be caused to trav l'by any convenient means, such as a motor 6 driving the framesupportingwheels? through gears 8, difierential gear, in a case 9, on shaft 10, and worm wheel 11.

Each runner frame 4 is caused to travel from the position shown at 15 in Figure 1, v

to the position 16' and is then removed to a return track 12, by means of which it-is brought back 'to its initial position over the tables. The frame 4, may be transferred from the operative track 5 to the return track .12. by any convenient means such as that shown, in which thetrack 5 is connected at each end to the track 12 by curved tracks 13, the outer rails being supported in their passage over the tables, (Figure 2).

Each runner is mounted on a vertical shaft 19 adapted to be turned in bearings 20 through a belt and gear drive 21 by a motor 22 mounted on. a frame 4. Any other form of runner may, howevcrfbe employed, such as a plurality of rotating discs mounted on a frame, or reciprocating blocks.

It is to be understood that on girders 14 p I a plurality of polishing runners 3 operate simultaneously,

, the following description however, it is assumed that runners such as are-shown in the drawings are employed, each runner being separated from the next by acertain space.

6 A paratus for the supply of POlIShlDg media to the runners are located at intervals along the apparatus, as at 23,24, 25, and the media are supplied to the runners 3 by conduits 26. 7 Each apparatus supplies 10 the same medium to the runners operating over a certain length of the apparatus in its neighbourhood. For instance, apparatus 7 23 may supply water in considerable quantity', 24 rouge and water, and 25 water in 15 small quantity. 7

According to this inventionvthe runners all travel at a constant speed, which, forthe purpose of this descri tron will be /assumed tobe half the speed of the glass.

v20,F\1 rther,it' will be assumed that each runner is to be subjected to-three di-fierent kinds of treatment, denoted by treatments 1, 2 and 3 and that, while subjected to these treatments it is to start operating on the a lass in threedi-fierent stages of the process, enoted by stages 1, 2 and 3 respectively,

the sta e after completion of the thirdbeing;

denote by 4. I Referring to Figures 3 and 4, X, Y, Figare 3) represents a length of lass w ic in a 'ven time,'travels to X in, (Figure 4).

- a, b, c, (l, e and f, at equal distances apart,

- namely. half the distance moved by the length-K, Y, in travelling to X Y. These runners are shown in Figure 3 as occupy ingupositions relative to the ground in cat by 'A, B,, C, D, E, F, respectively. Inthe given time, each runner moves into 40, the position previously occupied by the preceding runner, that is to say, into positions 4 B, C, D and so on. If, in Figure-l3, the

several divisions of the length of in the stages of'the processindicate by the Figures 1, 2, 3 connected therewith, and

further indicated by the superimposed horizontal lines, and if the several runners are to be subjected to the treatments denoted by r the Figures 1, 2, 3 connected therewith, the result of the operation of the runners on n the length X, Y, are six runners,

lass be with the divisions of the length of glass and with the runners in Figure 4. The runner f, having reached position G and'completed its operation with treatment 3 is removed from the operative track, while a runnereg comes into position. It will be seen that each runner operates successively with treatments 1, 2 and 3 during its operation on in stages 1, 2 and 3 respectively.

In the above description, three treatments and a'lratio of s eeds-of glass and runners of 2 to 1, have ecntaken (ml ,by way of example, and any desired num er (if trash ments may be given and any ratio of speeds, integral or fractional and "any number of runners may operate simultaneously with the same treatment. It is, however, to be observed that with certain ratios of speed and numbers of runners, the point at-which 00 each pair of divisions in which the glass is the final operation is completed, varies in position, but may be made to retain a 'fixed average position.

Having described my'invention, I declare that what I claim and desire to secure by Letters Patent is 1. In the process of continuous olishing of glass, moving the runners in tlie tion of motion of the, glass eta constant speed difierent from that of the glass and treatin their polishing surfaces successively wi I diflz'erent treatments at stages of travel of a rnnner',

2.",In' the process of continuous polishing of motion. of the glass at a constant speed difierent from that of the glass, treating their polishing surfaces successively with different treatments atdifferent stageeof travel of a runner, removing the runner from its operative position after tbe coniof glass, moving the runners in the direction pletion of its operative course and trans portin it by means which are clear of the succee ing runners to the start of'its openative course= I In. testimony whereof I have aflixed my signature hereto.

.rnnnnn'rc BARNES WALDRON. 

